368 



PROP. W. J. DA KIN ON THE 



Bridgetown, b}" a Mr. Lea and named by Fletcher (Proc. Linn. 

 Soc. N.8.W. 1895 (2) x.). Twelve years later, Peripatus w-as 

 found in anotlier locality niucli farther north, in the hills at 

 Armadale, only about 18 miles fiom Perth. Specimens of these 

 collected by Mr. H. M. Giles were sent to Professor Baldwin 

 Spencer. He found them to l^elong to a new species, and in a 

 short paper, published (12) in 1909, named it F. gilesii after tlie 

 collector. Specimens of the supposed third species had been 

 collected four years before this, i. e., in 1905, by a German 

 Expedition (The Hamburg Exped. of Michaelsen and Hartmeyer). 

 They were also collected near Perth and in tlie hills. These 

 specimens were sent to Boiivier, who wrote a detailed description 

 of the anatomy and discussed the relationships of the species to 

 other known Australian forms. Bouvier's paper (3) appeared in 

 1909, the same year in which S^jeucer's description of F. gilesii 

 was published. The supposed occurrence of two species in the 

 same district and the fact that both desci-iptions appeared in 

 the same year aroused the curiosity of the present author, and 

 the result of his investigations (see Proc. Zool. Soc. London, 

 June 1914) confirmed his suspicions. Per Ipato ides ivoodwardi 

 and Perij^ato ides gilesii turned out to be one and the same species, 

 and since Spencer's description was published some months before 

 Bouvier's paper, the name P. gilesii took precedence over 

 P. woodioardi. The fullest account of the species is, however, 

 to be found in the paper of Bouvier (3) under the name of 

 P. woodwardi. Now, since the previous publication of the writer 

 (Dakin, Proc. Zool. Soc. 1914), an exploration to the S.W. resulted 

 in the collection of over 100 specimens of the Peripatus first 

 made known from West Australia, i. e., PerijKUoides occidentalis. 

 The consequence was that the entire question was reopened. 

 About 100 specimens of P. gilesii were collected for the jjurpose 

 of a detailed examination and comparison of both species, the 

 northern and southern. The conclusion of this research was 

 rather surprising. In all the peculiarities that marked the 

 northern species (P. gilesii) the southern species agreed. The 

 difference between the two forms was so slight that we could not 

 regard them as more than varieties. 



Thus we have reduced the number of species of Perijxitoides in 

 West Australia from three to one. The southern type must 

 retain the name Peripatoides occidentalis — the northern form 

 should be known as Peripatoides occideiitcdis var. gilesii. Further 

 than this, however, a detailed investigation of the specimens has 

 shown that Bouvier's description of the anatomy contains several 

 inaccuiacies, some of which are decidedly important from the 

 point of view of comparisons. These inaccuracies are without 

 doubt excusable, for the number of specimens at the disposal of 

 Bouvier was small and the preservation could not ha\ e been all 

 that was to be desired. 



